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FEATURES OF THE COMPOSITION AND STRUCTURAL AND MORPHOLOGICAL CHARACTERISTICS OF THE ACTIVATED HYDROALUMOSILICATE OF THE POLYANSKOYE DEPOSIT

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 5-15 p.
Abstract
The results of a comparative study of the features of the material (chemical and mineralogical) composition and some surface characteristics of the enriched form of clay from the Polyana deposit subjected to activation by sulfuric acid treatment, as well as by exposure to IR- and UV-radiation are presented in this article. The initial clay material is accessible to polymineral rock with a predominance of montmorillonite hydroaluminosilicate in its composition (up to 75 wt %). There is IR and UV exposure to a significant change in the incoming composition of the clay, not observed. When an enriched form of clay is exposed to a solution of sulfuric acid, the proportion of cations (in particular calcium) in the exchange complex of clay decreases. In this case, a compensatory effect of protons on broken bonds localized on the surface of clay minerals is observed, which leads to a decrease in the absolute value of the electrokinetic potential on the surface of clay particles. Under IR- and UV-exposure of the clay material, a shift in the ξ-potential to the region of negative values is observed, which can be explained by the weakening of the bonds of exchange cations with the crystal lattice of montmorillonite, and, as a result, a change in the composition and structure of the interlayer medium. It was revealed that both UV and IR exposure to Polyanskaya clay leads to a decrease in the content of the proportion of freely bound water in the structure of montmorillonite hydroaluminosilicate. At the same time, treatment with UV-radiation significantly reduces the amount of OH-groups on the surface of the mineral due to the formation of siloxane bridges.
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ELASTOMERIC COMPOSITIONS BASED ON BUTADIENE-NITRILE RUBBERS WITH THE ADDITION OF A NEW OLIGOESTERAMIDE

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 16-25 p.
Abstract
The effect of air oxygen and several catalysts on the process of aminolytic destruction of polyethylene terephthalate by a mixture of amino alcohols (monoethanolamine and triethanolamine) at atmospheric pressure and convective heating is investigated. The terephthalic acid diamide obtained as a result of PET degradation is used as a monomer in the homofunctional polycondensation reaction. A new oligoesteramide containing an aromatic ring, two amide and hydroxyl groups in its structure was obtained. Its molecular weight was determined by a viscometric method. The use of the obtained oligoesteramide as a plasticizer in polar elastomeric compositions based on a mixture of butadiene-nitrile rubbers BNKS-40 and BNKS-28 is proposed. The effect on the kinetics of sulfur vulcanization and the viscosity of raw rubber mixtures is demonstrated. The acceleration of the vulcanization process has been revealed, as well as a decrease in the viscosity of rubber compounds, which contributes to a reduction in energy costs for processing and molding products. The change of elastic-strength parameters of vul-canized rubbers is substantiated. Comparison of rubber mixtures with oligoesteramide and plasticizers dibutyl phthalate, dioctyl phatalate and dibutylsebacinate was carried out. With the introduction of terephthalic acid oli-goesteramide, the elongation at break increases by 50-70 percent. The use of the obtained oligoesteramide as a plasticizer has an advantage relative to the selected comparison plasticizers, namely, the absence of "sweating" on the surface of the products during storage due to the higher molecular weight of oligoesteramide.
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ANALYSIS OF TRIPLE RECIPROCAL SYSTEMS BASED ON S1-ELEMENT NITRATES AND HALOGENIDES

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 26-38 p.
Abstract
Currently, the relevance of using more advanced and universal chemicals in the creation of electrolytes of heat carriers of non-melting salt mixtures and thermal batteries is increasing. Based on this, it can be stated with confidence that the halide and nitrate salts of s1-elements have the greatest potential in this direction. When developing the latest generators of electrical and thermal energy, such chemicals have a unique property - the abil-ity to run power plants even at low temperatures. For a wide practical application of melts of halides and nitrates of s1 elements with specified values of thermodynamic characteristics and physico-chemical properties, the study of phase diagrams is required. The method of differential thermal analysis was used to study the phase equilibrium of salt systems of the following type: Li,Rb||I, NO3, Li,K||Br,NO3, Li,K||I,NO3, Li, K||F,NO3, Li, K||Cl,NO3, Li,Rb||Br,NO3, Li,K||Br,NO3, Li,Na||I,NO3, Li,Rb||F,NO3. A comparative analysis of the series of three-component mutual systems formed from the systems experimentally studied by the authors of the article Li,K||F,NO3, Li,K||Cl,NO3, Li,K||Br,NO3, Li, K||I,NO3, Li,Na||F,NO3, Li,Na||I,NO3, Li,Rb||F,NO3, Li,Rb||Br,NO3, Li,Rb||I,NO3,Li,Cs||F,NO3, Li,Cs||Cl,NO3, Li,Cs||I, NO3 and systems studied by other authors Li,Na||Cl,NO3, Li,Na||Br, NO3, Li,Rb||Cl,NO3, Li,Cs||Br,NO3. The considered eutectic compositions of salt systems can be used to create a molten source of RHIT.
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EVALUATION OF EMULSIFIER EFFECT ON THE PROPERTIES OF WATER-BASED ALKYD EMULSION

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 39-48 p.
Abstract
The study is devoted to the issue of evaluating the effect of an emulsifier on the properties of the developed water-based alkyd emulsion intended for dust suppression. The goal was to establish a rational ratio of components in this system according to the following criteria: a decrease in the average droplet size, a decrease in relative viscosity, and an increase in sedimentation stability (emulsion life). The components of the basic composition of the emulsion were alkyd varnish (Resin GF-0123), surfactant (AMP-95), distilled water. To analyze the obtained compositions of the alkyd emulsion, dispersions were prepared containing: alkyd – 55-75% with a step of 5%; Surfactant – 0.1-0.5% in increments of 0.1% of the alkyd content (in-stead). The emulsion was obtained under the following technological parameters: emulsification temperature – 35°C, emulsification speed – 5000 rpm. The analyzed parameters were: dispersion (droplet size), viscosity, life (sedimentation stability) of the emulsion. It has been established that a rational composition, at which the minimum values of dispersion and viscosity are achieved, with a high lifetime at the maximum content of the polymer component, is a composition that includes: 59.7% alkyd, 40% water and 0.3% surfactant. The developed composition makes it possible to obtain an emulsion with a lifetime of more than 1 month, an av-erage dispersion value of 3 µm, and a viscosity of 40 mPa·s.
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SYNTHESIS OF GRAFT COPOLYMERS BASED ON SKF-32 BY ATOM TRANSFER RADICAL POLYMERIZATION

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 7-18 p.
Abstract
The use of partially fluorinated polymer electrolyte membranes in fuel cells is a very promising approach. Due to this, it is possible to avoid the disadvantages that arise when using perfluorinated polymers containing sulfonate groups as proton exchange membranes. Such disadvantages include high cost, unsatisfactory characteristics of proton transport with low water content and high values of hydrogen permeability through the membrane. Materials based on vinylidene fluoride are representative partially fluorinated polymers that exhibit interesting thermal, chemical, physical and technological properties. One of the promising directions for creating proton-exchange membranes is creation of graft fluoropolymers containing sulfonate groups. Samples of grafted copolymers based on industrial fluoroelastomer SKF-32 (a copolymer of vinylidene fluoride and chlorotrifluoro-ethylene) was carried out by grafting styrene with subsequent sulfonation. Graft poly(vinylidene fluoride-co-chlorotrifluoroethylene-g-styrene) was synthesized by atom transfer radical polymerization (ATRP). The data of viscometry and FT-IR spectroscopy allow us to conclude about the successful grafting of polystyrene fragments. Sulfonation of the grafted copolymer was carried out by injecting an acetyl sulfate solution to a polymer solution in 1,2-dichloroethane at a temperature of 40°C for 3 hours in an argon atmosphere. The qualitative composition, characteristic viscosity, molecular weight distribution and concentration of sulfogroups in the studied samples were investigated. The concentration of cross-linked polymer chains increases with an increase in the duration of synthesis, which complicates the sulfonation process. Optimal synthesis conditions were determined: temperature 90оC, initiator ‒ 2,2’-bipyridyl, duration – 3-4 h. Under these conditions, the highest yield of the finished product is achieved and unintentional crosslinking of the polymer does not occur.
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ISOLATION OF CELLULOSE FROM TYPHA LATIFOLIA BY THE NITRIC ACID DELIGNIFICATION METHOD

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 19-29 p.
Abstract
The material of the article considers the production of cellulose from broadleaf cattail by the nitrate method as one of the ways to process spent cattail after a cycle of filtration of water bodies in order to provide a potential effective natural biofilter in an economical way of disposal. Morphological differences of plants in composition, structure, packing density, conformation of molecules do not allow equally effective application of the same methods of material processing, which requires adjustment of the process conditions. For the nitric acid method, the process conditions were optimized in terms of the time parameters of soaking in solutions of nitric acid and alkali for its application to broadleaf cattail with the highest yield of the target product. The isolated cellulose by the nitric acid method satisfies the basic requirements for the content of α-cellulose and residual lignin to obtain a wide range of further products, including the synthesis of cellulose nitrates for the defense industry with the possibility of selecting processing conditions to obtain the required composition. Also, broadleaf cattail proved to be a relatively capacious source of holocellulose. The paper presents the mass fraction of holocellulose in samples subjected to different processing time parameters, the content of α-cellulose and residual lignin in holocellulose from broadleaf cattail.
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ANALYSIS OF MAGNETITE IN THE FE3O4/C NANOCOMPOSITE

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 30-41 p.
Abstract
This paper presents the magnetite study results of a Fe3O4/C nanocomposite obtained with air pyrolysis of a heterogeneous system which includes iron dichloride tetrahydrate – the source of magnetite nanoparticles (NPs) – and polyacrylonitrile (PAN) – the source of a carbon shell for nanoparticles protection from issues like aggregation. Methods such as Mössbauer spectroscopy and X-ray diffraction analysis are used for studying and determine the magnetite NP formation way. There are two types of NPs in the system studied: ferrimagnetic and superparamagnetic ones, the difference between which is clearly watched when taking Mössbauer spectra – sextets and doublets relatively. All magnetite NPs are established to be formed according to the reaction chain the inter-mediate elements of which is ferrous carbonate well-known for its decomposition into magnetite upon heating: FeCl2 → FeCO3 → Fe3O4. This transformation occurs in the temperature range from 200 oC to 400 oC above which an ability of the carbon shell to protect NPs is gradually reduced that leads to agglomeration and oxidation to hematite α-Fe2O3.
To study the magnetite obtained, size distribution of magnetite crystallites and the degree of nonstoichiometry are estimated. According to various calculations, the average crystallite size is 9-10 nm.
To preserve the NP properties, storage methods are important to be chosen properly, thence Mössbauer spec-troscopy of the Fe3O4/C nanocomposite is carried out after keeping it in air at room temperature for 1 year.
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PRODUCTION OF PHENOL-FORMALDEHYDE SORBENTS FROM LEATHER INDUSTRY WASTE

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 42-52 p.
Abstract
The leather industry refers to material-intensive industries in which the cost of raw materials is about 70-80% of the cost of finished products, therefore, the rational use of raw materials through waste disposal is of particular importance. 40-50% of the area can be used, the rest is usually sent for burial or incineration. Both in the first and in the second case, this is not only economically inefficient, but also an environmentally hazardous way to get rid of these wastes. One of the ways to dispose of such waste (minnow and sawn trim) is to process them into hydrolysates and use them in the production of gelatin, adhesives and building materials. In this paper, the possibility of using collagen hydrolysates as a modifier of phenol-formaldehyde resins has been studied. The sorption of heavy metal ions by an oligomeric sorbent obtained by modifying phenol-formaldehyde resins with collagen hydrolysate was studied at various pH values, temperature, particle sizes, and metal ion concentrations. The physical and technical characteristics of the adsorbent are determined.
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CORRELATION OF HYDROCARBON AND NON-HYDROCARBON COMPONENTS OF DISPERSED GAS IN THE PERMAFROST ZONE OF WESTERN SIBERIA

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 53-66 p.
Abstract
The composition of dispersed gas in the permafrost zone of Western Siberia characterized by the heterogeneity of the distribution of hydrocarbon and non-hydrocarbon components both over the area and along the section. This work carried out to assess the influence of the lithological composition on the following indicators: methane and its homologues, olefins and hydrogen. The analysis is based on a chromatographic analysis of 199 samples taken from 6 wells. A latitudinal well profile selected to capture as much diversity in lithology as possible within the work area. Samples taken at a site located within a multi-layer gas condensate field in the Nadymsky district of the Yamalo-Nenets Autonomous Okrug in the zone of continuous permafrost (PFR). To minimize the influence of external factors on the data obtained, a shallow well core used for the study, which underwent degassing and further chromatographic analysis to determine hydrocarbon components from C1 to C8, as well as non-hydrocarbon gases: hydrogen, carbon dioxide and helium. The work based on the results on hydrogen, olefins, methane and its homologues up to C7. Correlation schemes built based on the lithological composition, and then on the content of individual components in the wells, an inter-well correlation made with the distribution of indicators. As a result, it turned out that almost always at the boundary of lithological differences, the gas content values decrease, and the drop in values at the boundaries of layers of different composition does not affect the distribution of components within individual layers, that is, they do not accumulate in a significant amount, this phenomenon does not fall under the concept "geochemical barrier" in connection with which the concept of "geochemical screen" is proposed.
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DEVELOPMENT OF ELECTRODE MATERIALS BASED ON PLATINUM- RUTHENIUM NANOPARTICLES FOR METHANOL FUEL CELLS

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 7-15 p.
Abstract
The creation of effective materials for the functioning of new chemical power sources is currently an urgent task. Fuel cells can use environmentally friendly and energy resources, such as hydrogen and carbon biofuels (methanol and ethanol), which have a wide range of potential applications from portable devices to power plants. The researcher’s attention is attracted by the development of methanol fuel cells, due to their compact design, liquid fuel, low operating temperature and high specific power. However, commercialization of such energy sources is still a difficult task due to the high platinum content on the electrodes, the high cost of precious metals, low durability and delayed kinetics of both anode and cathode reactions. Increasing the activity and reducing the Pt load are two main tasks in the development of methanol fuel cell technology. In the work, bimetallic Pt-Ru nanoparticles were synthesized by chemical reduction in reversed microemulsions to evaluate the parameters of methanol fuel cells. A porous nickel was used as a carrier matrix, which was formed by template synthesis in a dimensional mask of metallic aluminum. As a result of experimental studies of methanol membrane-electrode assemblies of fuel cells based on porous nickel with Pt and Pt-Ru nanoparticles, it was concluded that the maximum voltage and current density are achieved when using electrodes based on platinum-ruthenium nanoparticles with a particle size of no more than 3 nm, a catalyst content of 0.2 mg/cm2 and a process temperature of 60oC.
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